Vembu StoreGrid 

Vembu StoreGrid is an extremely flexible Desktop Backup Software that works with your existing hardware. StoreGrid can facilitate trusted P2P, client-server & remote backups.
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Backup To Neighbor 

Backup To Neighbor is a network-based backup program, which contains a Client and Server Software. Server software is provided free of charge and peer-to-peer configuration is possible. It is a client-driven system.
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